Question

The sides of a triangle are 5 cm, 12 cm and 13 cm. What is its area?

Answer 1

s=5+12+13/2

= 30/2=15cm

area of triangle (herons formula)=√s(s-a)(s-b)(s-c)

=√15(15-5)(15-12)(15-13)

=√15x10x3x2

=√3x5x2x5x3x2

=√3²x5²x2²

=3x5x2

=30cm²

Answer 2

Answer:

Given :

The sides of a triangle are 5 cm, 12 cm and 13 cm.

In triangle ABC,

$\triangle$ABC,

AB,BC and AC are the sides of the triangle.

A = 5 cm

B = 12 cm

C = 13 cm.

We know that,

$\frac {a+b+c}{2} = \frac {5+12+13}{2}$

$\frac {30}{2} = 15 \: cm$

By using Heron's formula,

$A = \sqrt {15(15-5)(15-12)(15-13)}$

$A = \sqrt {15 × 10 × 3 × 2}$

$\Rightarrow$ A = 30 cm².